mRNA-Seq and miRNA-Seq Analyses Provide Insights into the Mechanism of Pinellia ternata Bulbil Initiation Induced by Phytohormones.

Pinellia ternata (Thunb.) Breit (abbreviated as P. ternata) is a plant with an important medicinal value whose yield is restricted by many factors, such as low reproductive efficiency and continuous cropping obstacles. As an essential breeding material for P. ternata growth and production, the bulbils have significant advantages such as a high survival rate and short breeding cycles. However, the location effect, influencing factors, and molecular mechanism of bulbil occurrence and formation have not been fully explored. In this study, exogenously applied phytohormones were used to induce in vitro petiole of P. ternata to produce bulbil structure. Transcriptome sequencing of mRNA and miRNA were performed in the induced petiole (TCp) and the induced bulbil (TCb). Gene Ontology (GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed for the identification of key genes and pathways involved in bulbil development. A total of 58,019 differentially expressed genes (DEGs) were identified. The GO and KEGG analysis indicated that DEGs were mainly enriched in plant hormone signal transduction and the starch and sucrose metabolism pathway. The expression profiles of miR167a, miR171a, and miR156a during bulbil induction were verified by qRT-PCR, indicating that these three miRNAs and their target genes may be involved in the process of bulbil induction and play an important role. However, further molecular biological experiments are required to confirm the functions of the identified bulbil development-related miRNAs and targets.

[Regularized inhomogeneity correction method for phased array image in magnetic resonance imaging].

Phased array coils (multiple receiver coil systems) have been extensively used for acquisition of MR images owing to their ability of increasing SNR, extending field-of-view (FOV), and reducing acquisition time. But the SOS algorithm,which is main method for phased array image reconstruction,will cause inhomogeneity in reconstructed image. A regularized least square method for phased array image combination is proposed in this paper. In the method, an additional reference scan is performed in advance. By using the reference scan, coil sensitivity map can be acquired, and image reconstructed from reference scan can be used as reference data in the regulation term. Experiments showed that the image uniformity was greatly improved by this method with scanning phantom and volunteer.